Micromanipulator for multilevel assembly

ABSTRACT

A micromanipulator for positioning a number of elements for multilevel assembly is achieved with a single displacement control mechanism. The mechanism functions to secure itself mechanically to ends of cantilever members to which the elements are secured, in turn, for manipulation. The arrangement may be thought of as a pair of ladders between corresponding rungs of which planks are laid. Individual planks can be extended by a vacuum system which fixes selected ends of the planks with respect to the two ladders and by moving one of the ladders.

United States Patent Michaelis 51 July 11, 1972 [54] MICROMANIPULATOR FOR MULTILEVEL ASSEMBLY [72] Inventor: Paul Charles Mlchlelb, Watchung, NJ.

[73] Assignee: Bell Telephone Laboratories, Incorporated,

Murray Hill, NJ.

[22] Filed: Dec. 4, 1970 [2|] Appl.No.: 95,057

[52] U.S.Cl.......... [51] lnLCl..... .i..

..................... .29/203 V, 29/DlG. 44 ..I-l05k 13/00 ss 1 Field oISearchZ ..29/203 v, 203 R. 010. 44

[56] References Cited UNITED STATES PATENTS Wanesky ..29/203 V 3,379,466 4/1968 Hughes ..29/203 V Primary ExaminerThomas H. Eager Attorney-R. J. Guenther and Kenneth B. Hamlin ABSTRACT A micromanipulator for positioning a number of elements for multilevel assembly is achieved with a single displacement control mechanism. The mechanism functions to secure itself mechanically to ends of cantilever members to which the elements are secured, in turn, for manipulation. The arrangement may be thought of as a pair of ladders between corresponding rungs of which planks are laid. Individual planks can be extended by a vacuum system which fixes selected ends of the planks with respect to the two ladders and by moving one of the ladders.

SCIamSDI-aWIngFlgum PATENTEUJUL 11 m2 3, 75,298 SHEET 3 BF a FIG. 5

MICROMANIPULATOR FOR MULTILEVEL ASSEMBLY FIELD OF THE INVENTION This invention relates to micromanipulating apparatus and more particularly to such apparatus for assembling multilevel devices.

BACKGROUND OF THE INVENTION Particularly in the electronics industry where circuits are becoming increasingly smaller, increasingly stringent requirements are placed on apparatus for handling the devices during assembly. This is particularly true if single wall domain devices are involved because the feature size of the elements of the devices is of the order of a fraction of a micron. That feature size imposes stringent positioning constraints for a variety of elements, such as detectors, and the like during fabrication of the devices. Domain wall devices are described in 1.1.5. Pat. No. 3,460,l 16 to A. H. Bobeck et al. issued Aug. 5, 1967.

The problem of correct positioning under such constraints is complicated by the fact that little room is available for maneuvering manipulative apparatus. For mechanized manipulators, for example, space allocations for displacement control mechanisms are tight. But typically, several independent mechanisms are required for multilevel assembly,

BRIEF DESCRIPTION OF THE INVENTION The present invention employs only a single displacement control which moves any one of a number of manipulator arms with respect to two support members. The arrangement may be thought of functionally as a pair of ladders between corresponding rungs of which planks are laid. In a most simple operation, one ladder is in a fixed position and the other is movable. The planks can be fixed or movable with respect to either ladder selectively. When a first plank, for example, is fixed with respect to the movable ladder and movable with respect to the fixed, a movement of the former toward the latter cantilevers the plank. If the first plank is then fixed to the fixed ladder and movable with respect to the movable ladder, the movable ladder may be moved away from the fixed ladder without withdrawing the first plank. Vacuum apparatus has been found completely suitable for fixing the planks with respect to the ladders.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a projection view of a multilevel micromanipulator in accordance with this invention;

FIGS. 2 and 3 are projection views, partially cut away, of portions of the micromanipulator of FIG. 1; and

FIGS. 4 and 5 are exploded and projection views of a device assembled by the apparatus of FIG. 1.

DETAILED DESCRIPTION FIG. 1 shows a micromanipulator arrangement in accordance with this invention. The arrangement comprises first and second stanchions 11 and 12 disposed normal to a support plane 13. The stanchions serve as the ladders mentioned above for manipulating planks or cantilever members 14 and 15. Only two cantilever members are described in the illustrative arrangement. It is to be understood, however, that others may be employed in an extension of the arrangement shown in FIG. 1.

Stanchion 1 I is fixed to plane 13 in the illustrative embodiment. Stanchion 12, on the other hand, is movable with respect to that plane. The base of stanchion 12 can be seen to comprise mating X and Y keyway guide members 17 and 18 for permitting such movement. The stanchion is moved along the keyways under the control of arm 19.

Arm 19 is an illustrative lever mechanism hinged at 20 to plane 13 and controlled by hand grip 21. Displacement of the hand grip in the X and Y plane is followed by stanchion 12 which is secured to arm 19 via arms 22 in FIG. 1 at the center line of stanchion 12. The arm, when moved, operates to physically displace stanchion 12 along the keyways defined by members 17 and 18. Arm 19 acts as a lever arm with a ratio 19a] 19b as shown in FIG. 1.

Arm 19 can be seen to comprise top and bottom portions 19'! and 19B fixed to one another only at 23 and spaced apart by sliding elements 24 and 25. The lower portion of the arm (19B) is hinged at points 24 and 26. Portion m functions to move stanchion 12 along an imaginery axis between stanchions 11 and 12. Portion 198, on the other hand, functions to move stanchion 12 along a second axis perpendicular to that axis. Physical movement of hand grip 21 towards or away from stanchion 12, for example, employs the lever ratio 28/27 and pivot point 26. Once positioned, hand grip 21 may be vacuum locked to support plane 13 by means not shown. Arm arrangements of this type are commercially available and are not described in further detail herein accordingly. Suffice it to say, that movement of stanchion 12 in the XY plane of support 13 is controlled by arm 19. Attention is now directed to the realization of multilevel manipulation of subassemblies by that movement.

The tops of stanchions 11 and 12 are adapted to receive U- shaped members 25 and 26 and 27 and 28, respectively. The U-shaped members define paths (or sleeves) in which the cantilever members 14 and 15 are guided.

Stanchions 11 and 12 are fitted to receive vacuum lines 30 and 31 as shown in FIG. 1. When a vacuum is supplied via line 30 or 31, element 14 is secured to stanchion 12 or 11, respectively. Each of the U-shaped members is connected to a vacuum line for supplying vacuums, similarly, for securing the member immediately thereabove as viewed in FIG. I. The various lines are connected to a vacuum generating ap aratus 32 for selectively producing the requisite vacuums.

The operation of such vacuums to selectively secure various elements together herein can be appreciated more fully from a consideration of FIG. 2. The end of vacuum line 31, for example, fits within stanchion 12 as shown in FIG. 2. When ap paratus 32 generates a vacuum through line 31, the recess 33 in member 14 is evacuated thus securing member 14 to stanchion l2. In the absence of such a vacuum, member 14 is free to move with respect to stanchion 12.

In like manner, members 14 and 15 may be secured to stanchions 11 or 12 via the vacuum lines shown in FIGS. 1 and 2 via recesses 33 or 33 of FIG. 3. In each instance, during an assembly operation each member is free at at least one end. Notice, in FIG. 1, if member 14 is fixed to stanchion 12 and free to move with respect to stanchion 11, any movement of stanchion 12 moves member 14 with respect to stanchion 11. If, alter such movement, member 14 is fixed with respect to stanchion 11 and free with respect to stanchion 12 and if member 15 is fixed with respect to stanchion l2 and free with respect to stanchion 11, any movement of stanchion 12 moves member 15 with respect to stanchion 11. Successive fixing and freeing of the ends of the various cantilever members permits the manipulation of piece parts at each of holding elements 40 and 41 of FIG. 1 for multilevel assembly.

Holders 40 and 41 are also adapted illustratively to be fixed to members 14 and 15 by vacuum lines 42 and 43 as shown in FIGS. 1, 2, and 3. Each such holder may include illustratively, an internal bearing surface 44 to support frames adapted to receive the piece parts (subassemblies) to be assembled.

In operation, the piece parts in suitable frames are placed within holders 40 and 41 and members 14 and 15 are manipulated in the X and Y directions with respect to one another along keyway guides 17 and 18 of FIG. 1 via movement of stanchion 12. Multilevel positioning to within 1 micron is achieved with the apparatus of FIG. 1.

Once a particular cantilever member, say member 14, is positioned by the movement of hand grip 21 via stanchion 12, the vacuum lock between member 14 and stanchion 12 is broken and member 14 is secured to stanchion 11 via vacuum apparatus 32 and vacuum line 30 of FIG. 1 instead. The vacuum in this instance is generated in recess 33' of member 14 as shown in FIG. 3; member 14 is in a fixed position and stanchion 12 is free to move without distributing the position of member 14.

Cantilever member 15 is now secured to stanchion 12 and released with respect to stanchion 11. Hand grip 21 is again moved to alter the position of member 15.

It is convenient for visual control to be maintained over the multilevel manipulation operations. To this end, the apparatus of FIG. 1 is disposed such that holders 40 and 41 fit within the jaws of a microscope (not shown) so that a base of an assembly may be secured to the microscope object plane for manipulation in the 2 direction and the positioning of the multilevel subassemblies by the apparatus of FIG. 1 may be viewed directly through the microscope.

FIGS. 4 and show exploded and assembled views of a multilevel device assembled in accordance with this invention. The device comprises a support member 70 (typically of glass) GLASS) on the surface of which a T-and-bar shaped magnetically soft overlay pattern 71 is deposited for the propagation of single wall domains. Such an overlay is described in copending application Ser. No. 732,705 of A. H. Bobeck filed May 28, I968 now U.S. Pat. No. 3,534,347. The support member is placed on the object platform P of the microscope at a position below holders 40 and 41 in FIG. 1. A magnetic wafer 72 in which single wall domains can be moved is inserted within and secured to holder 40 and a detector circuit 76 is secured to holder 41 for placement as shown in FIG. 4.

FIG. 4 shows a suitable spider support fixture 73 which includes an aperture into which wafer 72 is inserted. The fixture mates with recesses 74 in support surface 44 as shown in FIGS. 2 and 3 and is secured by vacuum via line 75 shown in FIGS. 2 and 4. FIG. 4 also shown a detection circuit 76 recessed within (the underside of) a fixture 77 secured, in turn, to holder 41. The fixture is secured by vacuum supplied to an annular channel 78 in FIG. 4 via line 79. The holders are now manipulated individually as described above, monitored by direct observation through the microscope.

Once the multilevel assembly is properly aligned, cantilevered members 14 and may be secured to both stanchions 11 and 12 via vacuum lines 30 and 80, and 31 and 81 shown in FIG. 2. In this manner, the relative positions of the subassemblies are fixed. The arrangement may, at this juncture be bonded together into a unit, protected by the original subassembly supports, by the bonds 81 of FIG. 5. Such bonds may be formed by familiar bonding tools through access ports, a representative one of which is shown at 82 in FIG. 4. The unit may be removed with spider fixture 73 forming an integral part of the unit for convenience of mechanical handling for later complete bonding of the entire periphery of the support members 70 and 77 together.

Element 70 has dimensions smaller than the inside diameter of holder 40 to permit withdrawal of the bonded device.

In an alternative assembly procedure, holder 40 may be reversed with the internal bearing surface 44 facing downward as viewed in FIG. 1. In this case, a subassembly is fitted, and secured by vacuum, conveniently within a mating spider support for assembly as described above. The assembled unit can be removed without the spider fixture affixed.

A recitation of the dimensions involved in the various subassemblies which constitute an assembled unit herein underscores the utility of a manipulator in accordance with this invention. Typically, a material in which single wall domains are moved is an inch on a side. The T-and-bar shaped overlay patterns have a period of 0.3 mil with a feature size of 1 micron and is carefully positioned with respect to the material. A detector is positioned to within 1 micron accuracy with respect to the position of one of the overlay elements. A vacuum of 7% 1/2 PSIG (pounds per square inch gauge) is sufficient to secure the subassemblies as described.

The apparatus as shown in FIG. I typically employs stanchions 7 inches by 2 inches by 2 inches spaced apart 4 inches. The sleeve formed by U-shaped member 25, for example, is 2% inches by 2 inches by one-half inch high. Arms 14 and 15 are typically 6 inches by 1% inches by one-eight inch with recesses 1 inch by l inch by one-sixteenth inch. The vacuum lines have an internal diameter of less than one-sire teenth inch developing a holding force of 7% psi between arm 14 and stanchion 12, for example, and a holding force of a couple of ounces between arm 14 and holder 40. An arm such as 14 weighs a few ounces and a typical holder weighs less than one ounce so that a vacuum of one-half atmosphere is more than adequate to secure the elements. A typical subassembly weighs much less than 1 ounce and, accordingly, is also easily secured in this manner.

Am 198 has a total length of about 17 inches between 20 and 21 of FIG. 1, 19', 19", and 27 being 2 inches, 10 inches, and 5 inches, respectively. Portion 19T has a total length of i3 inches, 28 being 2 inches long. A S-to-I ratio is achieved between the movement of hand grip 21 to stanchion 12.

An increased ratio is achieved if the top of hand grip 21 is made movable with respect to the bottom of the hand grip. A rod is hingeably secured to the center of both parts of the hand grip in this instance and where the rod intersects arm 19 defines a pivot point. The length of the rod from the arm to each center point determines the lever ratio which may be typically 200 w 1.

Of course, additional inputs, detectors and multilevel propagation circuits are positioned with like accuracy for uniting as described either with or without the spider fixtures secured to it.

FIG. 1 shows the illustrative mechanism for selectively securing the various subassemblies to include vacuum lines and vacuum generating apparatus 32 of FIG. 1. FIG. 1 shows a control panel for selecting the vacuum line by which vacuums are applied as required for operation. The control panel includes a plurality of switches S30, S31, S42, S43- where each designation includes the numerals of the vacuum line associated with the switch. The selection of a switch operates a solenoid valve 91, shown only at line 43 for applying the vacuum through that line. Each vacuum line is to be understood to include such a valve operated under the control of an asociated switch in panel 90.

No effort has been made to exhaust the possible embodiment of this invention. What has been described is considered only illustrative of the principles of this invention. Therefore, various embodiments can be devised by those skilled in the art in accordance with those principles within the spirit and scope of this invention.

What is claimed is:

l. A multilevel manipulator comprising, first and second support members, means for displacing said first support member along a first axis between said first and second support members, each of said members having a plurality of apertures therethrough defining sleeves, each of said sleeves having a geometry to permit slidable engagement with an arm member, corresponding ones of said sleeves in said first and second support members having centers along an axis parallel to said first axis, a plurality of said arm members slidably engaging corresponding sleeves, and means for selectively fixing the position of said arm members with respect to said first and second support members for selectively cantilevering said arm members when said first support member is displaced along said first axis.

2. A manipulator in accordance with claim 1 also including means for displacing said first support member in a plane including said first axis, each of said sleeves having a geometry to permit said arm members to be moved accordingly when secured to a support member moved in said plane.

3. A manipulator in accordance with claim 1 wherein said means for selectively fixing comprises vacuum generating means and means for selectively applying said vacuum to secure said arm members to said support members.

4. A manipulator in accordance with claim 3 wherein each of said arm members is adapted to receive a holder and means for securing said holders to said arms, each of said holders being adapted to receive a subassembly.

5. A manipulator in accordance with claim 4 wherein said means for securing said holders comprises vacuum generating means and means for selectively applying said vacuum to secure said holders to said arms.

a a s m r 5 

1. A multilevel manipulator comprising, first and second support members, means for displacing said first support member along a first axis between said first and second support members, each of said members having a plurality of apertures therethrough defining sleeves, each of said sleeves having a geometry to permit slidable engagement with an arm member, corresponding ones of said sleeves in said first and second support members having centers along an axis parallel to said first axis, a plurality of said arm members slidably engaging corresponding sleeves, and means for selectively fixing the position of said arm members with respect to said first and second support members for selectively cantilevering said arm members when said first support member is displaced along said first axis.
 2. A manipulator in accordance with claim 1 also including means for displacing said first support member in a plane including said first axis, each of said sleeves having a geometry to permit said arm members to be moved accordingly when secured to a support member moved in said plane.
 3. A manipulator in accordance with claim 1 wherein said means for selectively fixing comprises vacuum generating means and means for selectively applying said vacuum to secure said arm members to said support members.
 4. A manipulator in accordance with claim 3 wherein each of said arm members is adapted to receive a holder and means for securing said holders to said arms, each of said holders being adapted to receive a subassembly.
 5. A manipulator in accordance with claim 4 wherein said means for securing said holders comprises vacuum generating means and means for selectively applying said vacuum to secure said holders to said arms. 